The ultimate protection in extreme environments. Extra heavy terry loop construction surrounds the entire foot and leg for maximum warmth without the bulk. Over-the-calf in height, terry rib knit for custom fit. Reinforced heel and toe for increased durability. Elastic support knit into the arch for a foot hugging fit. Ideal for extreme cold weather conditions. Contents: 77% Merino Wool, 21% Nylon, 2% Lycra Spandex.